Switching off engine at traffic lights..?

Keith

But when would you turn it back on. Everyone knows you have to go on amber.

And also, which times would you turn it off. Slowing for a red light, engine off, crap the lights changed. Or would it be when you approach and the lights change as you do, then the guy behind you gets annoyed as you don't move off.

What a load of crap.

scbk

I sometimes switch the engine off when stopped at big roadworks on major roads/level crossings/bridges.

tomstickland

I did some google work and sums when someone asked how much fuel would be used sitting in their car for 40 minutes with the engine running. I worked out that on my commute I might make a 0.1mpg difference by turning the engine off at traffic lights.

balsingh

might work for some but if I did that in my car everytime I was at the lights, the stereo would switch off, electric aerial goes down, the doors would automatically unlock and the engine would immobilise (and would then need the remote fob pressing to switch the immobiliser off) ..... so basically, NO!!

Woodyrocks

I have to say I have been noticing this more and more lately. At first I thought people were just stalling left right and centre but it seems a lot of drivers are choosing to switch off there engines at the lights and not just at roadworks.

I find the theory that it would use up more gas starting it again than saved by switching it off an interesting one.

(Apologies for the terrible articulation. Think I should get myself off to bed!)

banger9365

a lott of the new car can do this like BMW's ,you must have see the advert on tv
http://www.bmw.co.uk/bmwuk/efficient_dynamics/bc/homepage/0,,___,00.html?bcsource=nationaltop
they call it atuo stop start for one
BMW efficient dynamics,where have i seen most of this,let me think most modern cars ,electric power steering,light weight engines,low friction fluids,reduced resistance tyres(so thats what they call them now),the one i like best is the brake energy regeneration any guesses what that is

Conor_3

Woodyrocks wrote: »

I find the theory that it would use up more gas starting it again than saved by switching it off an interesting one.

Back in ye olden days of carburretors, there was some truth in that. Fuel could empty out of the float chamber on a worn carb as it stood turned off. But now we've got very efficient fuel injection and engines which start virtually on the first turn of the flywheel, it's not the case anymore.

Conor_3

tomstickland wrote: »

I did some google work and sums when someone asked how much fuel would be used sitting in their car for 40 minutes with the engine running. I worked out that on my commute I might make a 0.1mpg difference by turning the engine off at traffic lights.

Actually it's more than that. I reset the trip computer after filling up once. If you stop at some lights etc within a few miles of doing that, you can watch the average MPG dropping 0.1MPG every few seconds.

vikingaero

The latest MINIs and BMWs with Efficient Dynamics have beefed up batteries, starters motors and alternators.

For us Average Joes with normal cars I'd only recommend switching off regularly:

once the engine has reached operating temperature,
where it is signed or recommended at level crossings,
if you are 2nd or 3rd or more in a queue to prevent delay to other motorists

hewhoisnotintheknow

probably yes

but if i did this each time i stopped my car would be stopped and started probably over 100 times a day, making my starter motor wear out 100 times quicker, probably not money saving